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Complex regional pain syndrome (CRPS) is a chronic pain condition characterised by prolonged, severe pain, disproportionate to inciting insult. Pain may be associated with changes and abnormalities in sensation, movements, skin colour and temperature and swelling in the affected area.
The incidence of CRPS has been reported as 5.46 cases per 100,000 persons, with increased frequency in women. It mostly involves peripheries without (CRPS 1) or nerve injury (CRPS2). The most common triggers are fractures, sprains/strains, soft tissue injury, limb immobilisation and surgical/medical procedures.
The pathophysiology is complex and poorly understood. Different mechanisms — for example, inflammation, vasoconstriction, hypoxia, central sensitisation and neuroplasticity — are involved in a complex network of interactions, resulting in a broad range of signs and symptoms. Diagnosis is purely based on clinical findings and fulfilling Budapest Criteria, which have high sensitivity and specificity. Proper neurological examination is mandatory to exclude radicular pain or peripheral neuropathy. Differentiating this pain from fracture and soft tissue pain is crucial and extensive radiological investigation is frequently unhelpful.
CRPS may result in long-term disability. NICE guidelines strongly support spinal cord stimulation (SCS) as treatment for CRPS.
Treatment of CRPS is challenging, partly because of a lack of clinical data regarding the efficacy of the various therapies. Initial treatment of CRPS is an integrated, multidisciplinary approach which includes pharmacotherapy, physical and occupational therapy and psychological support, such as CBT.
Common oral medications include paracetamol, NSAIDS, anticonvulsants, tricyclic antidepressants and opioids. However, such treatments seldom provide relief for significantly-advanced CRPS.
Sympathetic block, which has been considered as a standard treatment modality, may give no result or a very brief period of pain relief. Repeat blocks at frequent intervals carry increased risks of procedure-related complications. Implanting a SCS is often considered both an expensive and an invasive treatment, and satisfactory lead placement is necessary for successful treatment. However, SCS has been reported to have excellent results in the treatment of such refractory pain condition.
SCS for the treatment of chronic pain of CRPS is safe, appropriate, more cost-effective with a relatively low time to fiscal neutrality, and more effective when compared with conservative management and sympathetic blocks.
This case report supports the concept that rapid progression to neuromodulation, rather than delays, may better control symptoms and allow a more meaningful recovery.
A 43-year-old man presented in the pain clinic with a two-year history of severe, sharp, burning pain in the left ring and little fingers following a laceration injury with barbed wire at work. The patient was a farmer and had been unable to do his routine farm work. The laceration was surgically repaired under general anaesthesia, however severe pain persisted. Pain following repair of laceration was disproportionate to the inciting event.
The fingers looked dusky all the time and the pain prevented the wearing of gloves. He was unable to move the fingers without pain. Pain was continuous and could get worse at night and was also exacerbated by exposure to cold. Physiotherapy and medications, which included paracetamol, codeine, diclofenac, pregabalin, amitriptyline and tramadol, had provided no relief. A second exploratory surgery was performed but no treatable abnormality was found.
Physical examination revealed allodynia, hyperalgesia and flexion deformity of the ring and little fingers of the left hand. Routine blood results, x-rays and MRI scan of the neck were normal.
Nerve conduction study and EMG revealed mild sensory loss in the left ulnar nerve. The Budapest Criteria were fulfilled on the basis of disproportionate pain, colour changes, allodynia, hyperalgesia and differential diagnosis (See Table 1). He was diagnosed with complex regional pain syndrome.
Table 1: Budapest Criteria differential diagnosis
A Stellate Ganglion block was offered. The first gave analgesia for one day and the second SGB gave pain relief for a few hours only. The patient was offered spinal cord stimulation (SCS) treatment and was engaged in neuromodulation education programme in St James’s Hospital, Dublin. Successful trail and implantation of SCS was performed four years after his injury (Figure 1).
Figure 1: Implementation of spinal cord stimulation
He was discharged from the hospital after ensuring he was well able and educated to use the device. He is followed up in the pain clinic. The patient reported pain relief of 80 per cent and started to move his fingers actively.
Overall, he is very pleased with the treatment outcome, as it helped to control his pain and improve function. The patient is planning to return to farming.
- Pons T, Shipton EA, Williman J, Mulder RT. Potential risk factors for the onset of complex regional pain syndrome type 1: A systematic literature review. Anesthesiol Res Pract. 2015; 2015: 956539.
- Norman Harden R, Ann Louise Oaklande, Allen W Burton. Complex Regional Pain Syndrome: Practical diagnostic and treatment guidelines, 4th Edition, Pain Medicine, 2013 Feb; 14(2): 180-229.
- Birklein F, Schlereth T. Complex regional pain syndrome — significant progress in understanding. Pain, 2015 Apr; 156 Suppl 1:S94-S103.
- Harden RN, Bruehl S, Perez RS et al. Validation of proposed diagnostic criteria (the ‘Budapest Criteria’) for Complex Regional Pain Syndrome. Pain, 2010 Aug; 150(2):268-74.
- Geurts JW, Smits H, Kemler MA et al. Spinal cord stimulation for complex regional pain syndrome type I: A prospective cohort study with long-term follow-up. Neuromodulation, 2013, Nov-Dec; 16(6): 523-29.
- Poree L, Krames E, Pope J et al. Spinal cord stimulation as treatment for complex regional pain syndrome should be considered earlier than last resort therapy. Neuromodulation, 2013, Mar-Apr; 16(2): 125-4.